Mojtaba Mirakhorlo1, Mahmood Reza Azghani2, Sedighe Kahrizi3. 1. Department of Biomechanics, Faculty of Mechanical Engineering, Sahand University of Technology, Tabriz, Iran. 2. Department of Biomechanics, Faculty of Mechanical Engineering, Sahand University of Technology, Tabriz, Iran. azghani@sut.ac.ir. 3. Department of Physiotherapy, Faculty of Medicine, Tarbiat Modares University, Tehran, Iran.
Abstract
BACKGROUND: Lifting methods, including standing stance and techniques have wide effects on spine loading and stability. Previous studies explored lifting techniques in many biomechanical terms and documented changes in muscular and postural response of body as a function of techniques .However, the impact of standing stance and lifting technique on human musculoskeletal had not been investigated concurrently. METHODS: A whole body musculoskeletal model of lifting had been built in order to evaluate standing stance impact on muscle activation patterns and spine loading during each distinctive lifting technique. Verified model had been used in different stances width during squat, stoop and semi-squat lifting for examining the effect of standing stance on each lifting technique. RESULTS: The model muscle's activity was validated by experimental muscle EMGs resulting in Pearson's coefficients of greater than 0.8. Results from analytical analyses show that the effect of stance width on biomechanical parameters consists in the lifting technique, depending on what kind of standing stance was used. CONCLUSIONS: Standing stance in each distinctive lifting technique exhibit positive and negative aspects and it can't be recommended either one as being better in terms of biomechanical parameters.
BACKGROUND: Lifting methods, including standing stance and techniques have wide effects on spine loading and stability. Previous studies explored lifting techniques in many biomechanical terms and documented changes in muscular and postural response of body as a function of techniques .However, the impact of standing stance and lifting technique on human musculoskeletal had not been investigated concurrently. METHODS: A whole body musculoskeletal model of lifting had been built in order to evaluate standing stance impact on muscle activation patterns and spine loading during each distinctive lifting technique. Verified model had been used in different stances width during squat, stoop and semi-squat lifting for examining the effect of standing stance on each lifting technique. RESULTS: The model muscle's activity was validated by experimental muscle EMGs resulting in Pearson's coefficients of greater than 0.8. Results from analytical analyses show that the effect of stance width on biomechanical parameters consists in the lifting technique, depending on what kind of standing stance was used. CONCLUSIONS: Standing stance in each distinctive lifting technique exhibit positive and negative aspects and it can't be recommended either one as being better in terms of biomechanical parameters.